Environmental concerns have led to increased concern regarding the disposal of materials considered hazardous waste, including vehicle fluids such as engine oil, hydraulic oil, antifreeze, gear oil, transmission oil, fuel, and gas. As a consequence, special disposal methods, including recycling, have been developed for disposal of these fluids. For example, when an automobile service organization removes engine oil from a vehicle during an oil change, the oil is no longer "thrown away," but instead is collected so that it may be properly disposed of. The disposal of such filters also requires special handling because the filter contains a waste fluid which can harm the environment. If, however, the hazardous waste material can be removed from the filter, the disposal of the filter is less troublesome. Many such filters comprise a paper filter and a metal or plastic housing. Both these components may be recycled or otherwise disposed of in a conventional manner if the hazardous waste material is substantially removed from the filter. Therefore, it is desirable to develop a method for removing the hazardous waste fluid from such a vehicle filter.
One approach to removing oil from a used automobile oil filter is disclosed in U.S. Pat. No. 5,060,564. Rather than simply pressing downward on the oil filter so that the oil filter becomes flat thereby squeezing the oil therefrom, the oil extractor of U.S. Pat. No. 5,060,564 converts low pressure compressed air power to hydraulic power and uses a hydraulic source to draw a plate against the bottom of filter to squeeze the filter and remove the oil therefrom. Though this oil extractor is stated to meet Federal standards of 1990 mandating that 75% of the oil be removed from the filter prior to discarding the filter, the extractor is comprised of numerous costly components which may also require maintenance or repair. It is therefore desirable to develop an oil extractor composed of few working components to thereby minimize manufacturing, maintenance and repair costs. It is also desirable to provide a method of extraction which requires less energy than may be necessary to crush a filter composed of high strength materials, and which can extract more than 75% of the waste fluid in a filter.
The use of air pressure and a hydraulic source in the extractor of U.S. Pat. No. 5,060,564 also necessitates that precautions be taken to make certain that the air and hydraulic fluid do not leak to thereby maintain adequate pressure for squeezing the filter. These precautions are in addition to the mechanisms necessary to contain the oil extracted from the filter and may affect the potential for failure of the extractor. Also, the extractor utilizes a fluid, namely hydraulic fluid, which must also be safely disposed of. It is therefore desirable to develop an oil extractor which utilizes a power source which does not utilize a significant amount of a hazardous material for the generation of power and which only requires that precautions be taken to contain the oil extracted from the filter.